Apax bought about 37 percent of the firm in 2016 in tandem with investment firm NB Renaissance. The pair have since taken majority control and delisted the business from the Milan stock market.
Apax is now exploring strategic options to cash out of the company in a bid to take advantage of its strong performance, the sources said.
Rome-based Engineering - which serves various public sector institutions, banks, telecoms and utilities - is one of Italy's biggest technology firms providing anything from big data and analytics to business process management and cloud computing.
In 2017 its earnings before interest, taxes, depreciation, and amortisation (EBITDA) rose 13.5 percent to about 123 million euros while its revenues were up 10.1 percent to 1 billion euros.
A possible sale could be worth more than 1.5 billion euros, two sources said, representing a multiple of more than 12 times its 2017 core earnings. One source said Apax is targeting a valuation well in excess of that figure.
While a final decision has yet to be made, Apax has held preliminary talks with other private equity investors to gauge interest in a possible buyout, the sources said.
An initial public offering (IPO) is seen as another way to extract value from the business, one of the sources said, adding a return to the Milan bourse was first considered last year and remains an option.
Apax and NB Renaissance declined to comment.
Engineering employs about 11,000 staff and has been on a hiring spree in the past four years, recruiting about 1,000 people per year.
It plans to hire an additional 500 people by the end of the summer.
Apax has yet to select advisers and is expected to do so when it has received sufficient interest for the business to launch an auction process, likely to take place in the second half of the year, the sources said.
"It's on everyone's radar screen," a banking source said, adding bilateral discussions with interested parties were taking place.
"They're sounding out the market," another source said, pointing to a possible auction process after the summer.
Engineering, whose operations span Europe, the U.S. and Latin America, is led by Chief Executive Officer Paolo Pandozy.
Founder Michele Cinaglia still has 12 percent of the company while the balance is equally split between Apax and NB Renaissance.
Engineering has carried out a series of acquisitions in recent years to help boost growth.
Last year it bought Tuscan business process outsourcing specialist Infogroup to reinforce its domestic operations.
Apax has frequently invested in technology companies across Europe. On Feb. 26 it sold its stake in Dutch firm Exact Software to KKR.
In 2014 Apax bought Norwegian IT company Evry and subsequently delisted it from Norway's stock market, only to bring it back to the Oslo stock exchange in 2017.
(Reporting By Pamela Barbaglia; Editing by Elaine Hardcastle)
By Pamela Barbaglia, Stephen Jewkes and Arno Schuetze
